Journal of special operations medicine : a peer reviewed journal for SOF medical professionals最新文献

Background: Whole blood reduces mortality more effectively than blood component therapy in treating trauma. When cold-stored low-titer Type O whole blood (CS-LTOWB) is not available in austere environments, a walking blood bank (WBB) strategy is employed, with blood drawn from a local, pre-screened donor. Proper blood bag volume is essential for avoiding citrate-related complications; however, the optimal method for determining the correct blood bag volume is unclear.

Methods: Novices (n=65) and experts (n=10) at the 1st Marine Division each filled blood bags with the goal of hitting the target volume (450mL ±10%) using the 6.5" beaded cable tie (BC), 10" paracord (PC), and operator gestalt (OG) techniques. Filled bags were weighed on a digital scale. Correct fills, underfills, and overfills were assessed using nonparametric statistics at P=.05. Subjective assessments were also collected.

Results: For novices, OG achieved the highest rate of correct fills (69%), significantly outperforming BC (37%, P=.001) and PC (52%, P=.05). In experts, PC had the highest rate of correct fills (80%), though not significantly different from OG (70%, P=.59) or BC (50%, P=.08). OG was rated highest and was preferred by both groups. BC performed worst in objective and subjective measures for both groups.

Conclusion: BC performed poorly on all assessments and should be avoided. OG was generally superior to BC and PC, but was still suboptimal, with ~30% incorrect fills study-wide. Present findings demonstrate the need for better methods for determining donor blood bag fill volume to preserve the life of the wounded warfighter in WBB scenarios.

Introduction: The purpose of this literature review is to identify optimal alternative fresh frozen plasma thawing devices for Austere Resuscitative and Surgical Care (ARSC) teams operating in far forward settings constrained by logistical and operational requirements.

Methods: The authors reviewed existing literature to identify optimal alternative plasma thawing devices and assessed power consumption, weight, durability, portability, post-thaw coagulation preservation, and thaw kinetics. Field-adapted plasma thawers and other commercially available plasma thawing systems were analyzed to determine their suitability to meet the needs of ARSC teams. Sixteen articles were included after evaluating methodological quality and strength of evidence.

Conclusion: The authors recommend that ARSC teams use whole blood, liquid plasma, and FDA-approved thawing devices whenever available. However, if these options are not feasible, alternative methods should be considered to meet mission requirements. Among the devices reviewed, the sous vide demonstrated potential for this application. They are lightweight, compact, versatile, and capable of creating target temperature-controlled circulating water baths, making them superior when compared to other identified field-adapted devices. Dry-based thawing systems, such as the ZipThaw®, may also offer advantages by conserving resources like water and electricity; however, further research is needed to validate its effectiveness in forward operating environments.

Background: We evaluated arterial occlusiveness, 180° turns, pressures, reuse wear, and design aspects of four Ukrainian-manufactured tourniquets.

Methods: Strengthened Individual Combat Hybrid Tourniquets (SICH), TQ DNIPRO GEN 2s (DNIPRO), PULS tourniquets (PULS), and Yellow&Blue tourniquets (Y&B) were each applied to left/right, mid-arm and mid-thigh, of 30 recipients, 100 seconds first-completion-to-release. Results were compared to concurrent study X8T-T2G (n=40).

Results: All applications reached occlusion. Some thigh Y&B could not be secured: 1 never; three after additional turn. Twenty-six arms, 43 thighs needed an additional turn (median total turns arm 1.5 SICH, DNIPRO, PULS; 2.5 Y&B and thigh 2.5 SICH, DNIPRO; 2.0 PULS; 3.5 Y&B; p<.0001 others versus Y&B; X8T-T2G arm 0.7, thigh 1.5, p≤.0004 versus Ukrainian-manufactured). Ukrainian tourniquets pre-release, 39 arm and 83 thigh were >500mmHg (median range: occlusion arm 255-274mmHg, thigh 398-423mmHg; first completion arm 349-588mmHg, thigh 474-572mmHg; pre-release arm 350-638mmHg, thigh 517-583mmHg). No X8T-T2G >500mmHg (median pre-release arm 304mmHg, p<.002 versus SICH, DNIPRO, PULS and p=.522 versus Y&B; thigh 367mmHg, p<.0001 versus Ukrainian-manufactured). For per-turn pressure increases arm>thigh (p<.0001) and additional turns>turns-to-first-completion (p<.0001). Y&B concerns: stitching failures at rod-loop and limb-encircling strap connection; clip bending; potential slider-redirect-buckle-pieces loss, incorrect slider-redirect-buckle rethreading, and windlass-rod removal; and rod-securing inability. On 44.2-75.0cm-circumference thighs, hook-and-loop-strap-base-area-strap-securing mechanisms were not reached on 39% of applications.

Conclusions: The SICH, DNIPRO, and PULS always reached completable arterial occlusion; Y&B did not and had design concerns. None became nonfunctional. Windlass-rod-tightening-system tourniquets routinely have higher-than-desirable completion pressures, which matters with long tourniquet times. Current hook-and-loop-limb-encircling straps are too short to engage base-area-strap-securing mechanisms on many adult thighs.

Background: Trauma in combat or civilian settings often involves severe hemorrhage and open wounds, which carry a high risk of infection. Current clinical guidelines recommend prophylactic antibiotics for high-risk wounds. Adequate plasma antibiotic concentrations are necessary for tissue penetration, particularly into injured tissue. Blood loss from traumatic hemorrhage may impact plasma antibiotic concentrations. However, the association between blood loss, subsequent blood product transfusion, and antibiotic concentrations remains unclear. We hypothesize that antibiotic concentrations decrease in proportion to the volume of blood transfused, potentially leading to insufficient antibiotic concentrations, placing the injured patient at increased infection risk.

Methods: We are conducting a prospective, multicenter study that will enroll trauma patients from two large trauma centers: Brooke Army Medical Center and the University of Colorado Hospital. We will enroll participants receiving antibiotics for wound prophylaxis and three or more units of blood products. We will also enroll a control arm comprised of participants receiving the same antibiotics who receive two or fewer units of blood. Blood samples will be collected from participants at predetermined time intervals after antibiotic infusion to assess antibiotic concentrations. Our statistical analysis will focus on the relationship between the volume of blood products administered and antibiotic concentrations. Results will inform the development of antibiotic dosing models for clinicians that adjust for the effects of blood transfusion.

Conclusion: The goal of this study is to fill a significant gap in trauma care that could potentially lead to optimized antibiotic dosing and improved outcomes for trauma patients.

The prehospital administration of low-titer O whole blood (LTOWB) has gained attention as a lifesaving intervention in trauma care, demonstrating associated significant survival benefits over traditional crystalloid and component therapies. Despite a growing body of evidence from both military and civilian studies supporting its efficacy, safety, and feasibility, LTOWB continues to face criticism. This article examines commonly raised objections, including concerns over patient identification, blood rewarming, transfusion reactions, and potential risks for childbearing women. Emphasizing the need for transparency and evidence-based progress, this article advocates for the integration of LTOWB into prehospital protocols, positioning it as a crucial advancement in emergency medical services and trauma care.

Background: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an endovascular technology indi-cated for temporarily controlling traumatic life-threatening, noncompressible abdominal, truncal, or pelvic hemorrhage. Through percutaneous access or cut-down to the femoral artery, an intra-aortic balloon catheter is fed into the aorta and inflated, occluding distal blood flow and, thus, bleeding. To determine specific barriers to REBOA in deployed environments, we conducted a quality improvement project and survey of ER-REBOA® placement and monitoring capabilities at four medical treatment locations in Iraq and Kuwait during the spring of 2019.

Methods: The primary objective was to evaluate each in-theater medical site's ability to deploy REBOA, which was defined as having a provider capable of placing REBOA and the minimum equipment necessary. The investigators interviewed providers and through self-reported surveys, determined the personnel capable of placing a REBOA. REBOA equipment and monitoring equipment were identified through direct inspection of sites and interviews with logistical and equipment staff.

Results: A total of 113 individuals participated in the evaluation and training. Three of the four sites had the minimum training and equipment requirements to complete the procedure: one REBOA-capable provider, an unexpired ER-REBOA® device, and an unexpired introducer catheter kit. Overall, 6 out of 32 physicians (18.7%) were capable of placing an ER-REBOA.

Conclusion: This deployed site survey demonstrates that the minimal requirements and personnel for ER-REBOA placement were met at most studied locations in 2019. However, improvements in pre-deployment training of select medical personnel in REBOA and arterial blood pressure monitoring are recommended to ensure adequate resourcing and redundancy in training.

Background: Current triage practices in military mass casualty (MASCAL) events are frequently misaligned with real-world operational needs, leading to delays, confusion, and suboptimal outcomes. Despite the existence of formal triage systems, field responders often default to simplified methods that emphasize speed, clarity, and survivability. This review supports the Committee on Tactical Combat Casualty Care (CoTCCC) recommended transition to a principles-based, two-pass triage system optimized for Role 1 prehospital environments.

Methods: A multi-modal analysis incorporating retrospective case reviews, field surveys, and doctrinal review was conducted to evaluate real-world triage practices across recent military MASCAL incidents. Findings were synthesized to develop an updated triage methodology anchored in clinical judgment, tactical relevance, and operational simplicity.

Results: In 93% of reviewed MASCAL cases, formal triage tools involving color-coded tags and five-category algorithms were not used. Responders preferred a binary or simplified categorization (e.g., urgent vs. nonurgent) for rapid decision-making. The proposed two-pass system includes an initial "first pass" to identify casualties requiring immediate life-saving intervention and a more deliberate "second pass" to sort casualties into urgent, priority, or routine categories aligned with established evacuation precedence. This model emphasizes rapid assessment via the Massive Hemorrhage, Airway, Respirations, Circulation, Hypothermia/Head Injury (MARCH) framework, clear communication between medical and nonmedical personnel, and dynamic re-evaluation as conditions evolve.

Conclusion: The principles-based two-pass triage model offers a practical and operationally aligned framework for Role 1 casualty care. It improves decision-making, communication, and casualty flow during complex MASCAL events while enhancing training, interoperability, and mission success. This approach is endorsed by CoTCCC and integrated into the 2025 TCCC guidelines to optimize outcomes across the full spectrum of military operations.

Introduction: Severe hemorrhage, notably non-compressible torso hemorrhage (NCTH) leading to hemorrhagic shock and traumatic cardiac arrest (TCA), represents a critical and challenging condition in trauma resuscitation. Despite advancements in hemorrhage control for extremities, NCTH continues to present a significant barrier to survival, particularly in the prehospital setting. The abdominal aortic and junctional tour-niquet (AAJT), an external hemorrhage control device, has emerged as a promising tool for addressing junctional and abdominal hemorrhages, yet its clinical effectiveness remains inadequately explored. This review assesses the efficacy of the AAJT in improving survival rates in patients with hemorrhagic shock.

Methods: A systematic literature search was conducted per PRISMA guidelines. Only English-language publications published between 2019 and 2024 were included.

Results: Of the nine relevant publications identified, one was a descriptive case series, seven were animal model studies, and one examined the practicality of the AAJT when tested by combat medic technicians.

Conclusions: The sparse literature did not permit a proper systematic analysis or conclusions on the clinical effectiveness of AAJT in human patients. The AAJT remains a forward-thinking and viable option for improving trauma resuscitation protocols. Further studies, particularly randomized and controlled clinical trials, are required to advance this research.

Background: Heat loss through intravenous (IV) tubing during a fresh whole blood (FWB) transfusion in austere environments can result in unhealthy fluid administration temperatures for patients. This research study aimed to quantify the amount of heat loss through the IV tubing during austere blood transfusions and propose mitigation methods, such as utilizing thermal insulation around the IV tubing and reducing the overall length of the tubing.

Methods: Experiments were conducted in an environmental chamber where fluid temperature was controlled at the inlet of the IV tubing, while the resulting outlet fluid temperatures and volumetric flow rates were measured. The temperature within the environmental chamber was systematically reduced by 3°C from the first collection starting at 20°C to a final collection at -39°C.

Results: Heat loss analysis revealed that 40.9 (SD 3.4) W of heat was lost, even when the ambient temperature was 20 °C. As the environmental temperature reached -39°C, the heat loss through the IV tubing increased to 168 (SD 17.4) W.

Conclusion: Significant heat loss occurs through IV tubing during blood transfusions in cold austere environments. Mathematical models suggest that thermal insulation around the IV tubing and reducing overall tubing length could effectively mitigate these losses.

Background: We hypothesized shared-design tourniquet features have useful first-use learning when knowledge-of-results occurs.

Methods: In a prior study, after watching training videos, 64 volunteers were videoed applying (Latin squares randomization): Combat Application Tourniquet Generation 7 ™ (CAT7), SOF ™ Tactical Tourniquet-Wide Generation 3 (SOFTTW3), SOF™ Tactical Tourniquet-Wide Generation 5 (SOFTTW5), Tactical Mechanical Tourniquet® (TMT), OMNA Marine Tourniquet™ (OMT), X8T-Tourniquet (X8T), Tactical Ratcheting Medical Tourniquet™ (Tac RMT), and RapidStop® Tourniquet (RST). Tourniquets were applied to live thighs with audible distal Doppler pulses.

Results: This study subset was 10 experienced and 33 no-experience appliers. Experienced appliers had fewer strap/redirect and fewer tightening-system understanding problems and faster associated times than no-experience appliers. Among no-experience appliers, firstuse learning was supported by faster "Go" to "strap secured" times for combined seventh and eighth versus first applications (p=.008), secondversus first-encounter CAT7/OMT applications (p=.0005), and secondversus first-encounter SOFTTW3/ SOFTTW5 applications (p=.079). Occlusion at "Done" was more frequent with experienced appliers (p=.006) and did not show first-use learning across all tourniquets in no-experience appliers. Occlusion at "Done" indicated possible first-use learning with ratcheting-buckle versus windlass-rod tightening systems (p=.028, no-experience appliers). Hook-and-loop strap security, which provides no inherent knowledge-of-results, showed no learning in experienced (five problem applications by two appliers) or no-experience appliers (29 problem applications by 18 appliers).

Conclusions: Knowledge-of-results is critical for, but does not guarantee, tourniquet-application-useful first-use learning. The existence of first-use learning can allow limited experience with one tourniquet to improve performance with a different tourniquet with shared-design features. Therefore, exposure to different designs may have value, and providing tourniquet-training knowledge-of-results is important.